Hall generators have been used in magnetic field sensing systems to generate an output voltage or so-called Hall voltage which is a function of a magnetic field applied perpendicular to the surface of the Hall generator. At right angles to this direction, a drive current is passed through the Hall generator and at right angles to the current flow, via signal contacts, the Hall voltage can be tapped from the Hall generator. The Hall field sensor shows an undesirable temperature drift of the Hall voltage.
It is known, in order to compensate for the temperature drift of the Hall voltage, to provide an input resistor in series with a constant voltage generator for the drive current path of the Hall generator. In this case, the drive current traversing the generator increases with increasing temperature of the sensor because of the negative temperature coefficient of the resistance of the drive current path. The resulting reduction with increasing temperature of the Hall voltage is thereby counteracted.
While this circuit has been found to be marginally effective in compensating for temperature drift, it is not entirely successful and the circuit does not allow for other advantages, for example a linearization of the characteristic of the sensor.